Buggy code:
public abstract class PathManagerService implements PathManager , Service < PathManager > { public static final ServiceName SERVICE_NAME = JBOSS . append ( "path" , "manager" ) ; private final Map < String , PathEntry > pathEntries = new HashMap < String , PathEntry > ( ) ; private final Map < String , Set < String > > dependenctRelativePaths = new HashMap < String , Set < String > > ( ) ; private final Map < String , Map < Event , Set < Callback > > > callbacks = new HashMap < String , Map < Event , Set < Callback > > > ( ) ; protected PathManagerService ( ) { } public final void addPathManagerResources ( Resource resource ) { } public final String resolveRelativePathEntry ( String path , String relativeTo ) { } @ Override public final Handle registerCallback ( String name , Callback callback , Event ... events ) { } @ Override public final void start ( StartContext context ) throws StartException { } @ Override public final void stop ( StopContext context ) { } @ Override public final PathManagerService getValue ( ) throws IllegalArgumentException , IllegalStateException { } protected final ServiceController < ? > addHardcodedAbsolutePath ( final ServiceTarget serviceTarget , final String pathName , final String path ) { } public final PathEntry getPathEntry ( String pathName ) { } final void changePathServices ( final OperationContext operationContext , String pathName , String path ) { } final void changeRelativePathServices ( final OperationContext operationContext , String pathName , String relativeTo ) { } final List < PathEntry > getPaths ( ) { } final void removePathService ( final OperationContext operationContext , final String pathName ) { } final void removePathEntry ( final String pathName , boolean check ) throws OperationFailedException { synchronized ( pathEntries ) { PathEntry pathEntry = pathEntries . get ( pathName ) ; if ( pathEntry . isReadOnly ( ) ) { throw ControllerMessages . MESSAGES . pathEntryIsReadOnly ( pathName ) ; } Set < String > dependents = dependenctRelativePaths . get ( pathName ) ; <START_BUG> if ( dependents != null ) { <END_BUG> throw ControllerMessages . MESSAGES . cannotRemovePathWithDependencies ( pathName , dependents ) ; } pathEntries . remove ( pathName ) ; triggerCallbacksForEvent ( pathEntry , REMOVED ) ; if ( ( pathEntry . getRelativeTo ( ) ) != null ) { dependents = dependenctRelativePaths . get ( pathEntry . getRelativeTo ( ) ) ; if ( dependents != null ) { dependents . remove ( pathEntry . getName ( ) ) ; if ( ( dependents . size ( ) ) == 0 ) { dependenctRelativePaths . remove ( pathEntry . getRelativeTo ( ) ) ; } } } } } final ServiceController < ? > addAbsolutePathService ( final ServiceTarget serviceTarget , final String pathName , final String path , final ServiceListener < ? > ... listeners ) { } final ServiceController < ? > addRelativePathService ( final ServiceTarget serviceTarget , final String pathName , final String path , final boolean possiblyAbsolute , final String relativeTo , final ServiceListener < ? > ... listeners ) { } final PathEntry addPathEntry ( final String pathName , final String path , final String relativeTo , final boolean readOnly ) { } final void changeRelativePath ( String pathName , String relativePath , boolean check ) throws OperationFailedException { } final void changePath ( String pathName , String path ) { } private void addDependent ( String pathName , String relativeTo ) { } private PathEntry findPathEntry ( String pathName ) { } private void triggerCallbacksForEvent ( PathEntry pathEntry , Event event ) { } PathManagerService . PathEventContextImpl checkRestartRequired ( OperationContext operationContext , String name , Event event ) { } private void getAllDependents ( Set < PathEntry > result , String name ) { } private void getAllDependentsForRestartCheck ( Set < String > result , String name ) { } private final PathResolver absoluteResolver = new PathResolver ( ) { @ Override public String resolvePath ( String name , String path , String relativeTo , PathResolver resolver ) { } @ Override public boolean isResolved ( String relativeTo ) { } } ; private final PathResolver relativeResolver = new PathResolver ( ) { @ Override public String resolvePath ( String name , String path , String relativeTo , PathResolver resolver ) { } @ Override public boolean isResolved ( String relativeTo ) { } } ; private class HandleImpl implements Handle { private final String pathName ; private final Callback callback ; private final Event [ ] events ; public HandleImpl ( String pathName , Callback callback , Event ... events ) { } public void remove ( ) { } } static class PathEventContextImpl implements PathEventContext { private final OperationContext operationContext ; private final Event event ; private volatile boolean reload ; private volatile boolean restart ; PathEventContextImpl ( OperationContext operationContext , Event event ) { } public boolean isBooting ( ) { } public boolean isNormalServer ( ) { } public boolean isResourceServiceRestartAllowed ( ) { } public void reloadRequired ( ) { } public void restartRequired ( ) { } @ Override public Event getEvent ( ) { } void revert ( ) { } boolean isInstallServices ( ) { } } }

Fix:
if ( check && ( dependents != null ) ) {